Electric switch



T. L. LEE,

ELECTRIC SWITCH.

APFUCATIDN mm APR. 10. me.

Patent/ed Sept. 21, 1920.

Wm M7 'rnouas L. ma n,

COMPANY,

OF ROCHEfiTEB. NEW YORK, OF ROCHESTER. NEWYORK, A CORPORATION OF NEW YORK.

ASBIGNOR TO NORTH sas'r ELECIIHC ELECTRIC Speolfloatlen of Letters Patent.

Patented hopt. 2|. main.

Armin-non ma April 10, me. Berle] no. 90am.

To all whom it"mmi concern:

Be it known that I, THOMAS citizen of the United States Rochester, in the county of 5 State of New York, have invented. certain new and useful Switches; and I lowing to be a full, clear,

1m do tion of the invention such.

the art to which it apperothers skilled in tains to make and use This invention relates L. Lee, a residing at onnoe and rovements in Electric ereby declare the foland exact descrip' as will enable the same.

to electric switches adapted. for handling comparatively heavy currents,

- switch are liable to wear where the contact-surfaces of the and destruction due to arcin and to mechanical causes.

The 0 ject of the invention is to a switch in which the operative sur contact-mem the stationary readily renewed end stationary vention, which without the replacement of parts of the switch.

)roduce aces of hers may be substitu i ion or 0 this contact-members are employed, in accordance with the Present inare so mounted, and-so re- 26 lated to the movable contact-members, that rtions only of their heads 0 d by the movable contactaces are engage members, and that tl ma' be changed and t rotation of the s tia members.

r working surie portions so engaged has renewed by partationary contact- In the accompanying drawings Figure .1

of the switch,

contacts and thei The invention 40 her 5 of laminated sheetoperates with bars comprising wide heads 6. The membe carried at the lower on slides through a guide end of the stem .in a sleeve in bar and the hea -1, menin es) be circuit through the the switch-c rfa partly in section. of a t e present invention;

the base-plate the stationary is illustrated'as embodied in a switch having a movable contact-memis provi d 10, norina metal, which two stationary contact-memfiat rectangular metal r 5 is fixed in a clip 7, d of a stem 8 which bar 9. The upper (led with a head 10 depressed to close the switch; lbehead asing 11, which bar 9. A compresbetween the guideslides lly retains the ring movable contort-n\cmher in raised position. as shown in Fig. l,

The stationary contact members are mounted on the base-plate 14 of the switchcusing, and for this purpose. and also to connect them with the conductors of the circuit which is controlled by the switch, each stationary contact-member is provided with a stem 13 which )asses through an opening in the base-plate,l1ut is insulated therefrom. as shown in Fig. 1.. Nuts 18 iii; the slum in place, and nuts 19 are provided for bind in% wires to the stems in the usual manner he heads 6 of tlie'stationnry coolant members are made rectangular in fonn and of such width that only approximately one half of their surfaces are engaged by the movable contact-member 5 l of the stationary contaot members. Accordingly, the wear incident to the use of the switch occurs only upon the outer halves of the working surfaces of the stationary contact'membcrs. have been worn away the nuts 18 may be loosened. and the stems and the heads of the stationary contact-members may be then given a, half-rotation. whereby fresh p tions of the working-surfaces are brought into coiiperative relation with the movable contact-members] For the purpose of normally preventing rotation of the stationary contact-uu-mlwis.

a. stri 15 of sheet-metal is employed. this strip mg perforated near its ends. so that it may interposed between the heads ('1 and the base-plate 14. A strip of insulatmaterial 16 is interposed bclween the strip 15 and the heads (i. and the ends of both of the strips 15 and 16 are bent upwardly, at right angles. so as to form flanges, which closely embrace the outer edges of the heads 6 and thus positively prevent. rotation of these heads under normal conditions. Such rotation may be performed, however. when the nuts 18 have been loosened and backed of sufficiently .to permit the heads to be raised clear of the flanges 17.

claim:

An electric switch comprising: a first contact-member; a support; a second contact-member mounted on the support and in any position When these outer halvemm having a stem and a fiat contact-surfatm normal tip the axis of the stem, said surface beinfubstantially gredter than that of the oontact-member and ecoentrically 5 disposed with relation thereto; and means,

on the su port, normally pxeven'ting romtiop of t e.aecond contact-member, said member being disengageable from said means and rotatable, when so disengaged, about the axis of its stem to bring a fresh 10 portion of its contra-surface into cooperative relation with first contact-member.

THOMAS L. LEE. 

